Miss Mu Is Beautiful and Daring!

She is aloof. She is gentle and adorable. She is ruthless. He is less aloof than she is. He is a warm-hearted flirt. He is kind only to the people he loves. Three assassins, three heartthrob students loved by everyone. One couple has been together since middle school, while the other two pairs start arguing the moment they meet. After spending a semester together, they all fall in love with one another. In the end, they get married on the same day, in the same month, and in the same year they were born.